Class 7 Science worksheet on waste water management, featuring questions, a diagram, and household tips.

Solution to the Worksheet: Waste Water Story (Class 7)

#### Q.1 Fill in the blanks:

1. The impurities like lather, oil, urea, dirt etc. Which are dissolved and suspended in sewage are called _________.
- Answer: Pollutants
- Explanation: Pollutants are substances that contaminate water and make it unsafe for use. These include dissolved and suspended impurities like lather, oil, urea, and dirt.

2. The set of pipes which take away sewage from our homes to the water treatment plants are called _________.
- Answer: Sewerage system
- Explanation: The sewerage system is a network of pipes designed to collect and transport sewage from homes, industries, and other sources to treatment plants.

3. _________ is wastewater released by homes, industries, hospitals etc.
- Answer: Sewage
- Explanation: Sewage refers to the wastewater generated from households, industries, hospitals, and other sources, which contains various pollutants.

4. _________ trees are planted all along sewage ponds.
- Answer: Eucalyptus
- Explanation: Eucalyptus trees are often planted near sewage ponds because their roots absorb large amounts of water, helping to reduce the water level in the ponds.

5. Wastewater is treated in a _________ treatment plant.
- Answer: Sewage
- Explanation: Wastewater is treated in a sewage treatment plant, where it undergoes processes to remove pollutants and make it safe for reuse or discharge into natural water bodies.

---

#### Q.2 Complete the chart:

The chart asks you to list different uses of clean water. Here’s how you can fill it:

```
Water can be used as
Clean Water put to Use
/ | \
/ | \
/ | \
Cooking Washing Bathing
| | |
| | |
Drinking Cleaning Irrigation
```

- Uses of Clean Water:
1. Cooking
2. Drinking
3. Washing
4. Bathing
5. Cleaning
6. Irrigation

---

#### Q.3 Identify the following statements as "Do's and Don'ts" for better housekeeping practice:

1. Cooking oil and fats should be thrown down the drain.
- Answer: Don’t
- Explanation: Cooking oil and fats can clog drains and sewers, leading to blockages and backups. They should not be disposed of through the drainage system.

2. Chemicals like paints, solvents, insecticides, medicines, motor oil may kill microbes that help to purify water, so do not throw them down the drain.
- Answer: Don’t
- Explanation: Hazardous chemicals can harm the environment and kill beneficial microorganisms in water treatment systems. They should never be disposed of through drains.

3. Used tea leaves, solid food remains, soft toys, cotton, sanitary towels etc. should be thrown in the drains.
- Answer: Don’t
- Explanation: Solid waste items like tea leaves, food remains, and non-biodegradable materials can block drains and cause plumbing issues. They should be disposed of in trash bins, not drains.

4. The untreated human excreta is a health hazard, thus toilets should be constructed to maintain personal hygiene.
- Answer: Do
- Explanation: Proper sanitation, including the construction of toilets, helps prevent the spread of diseases caused by untreated human waste. This is an essential practice for maintaining personal and public health.

---

Final Answers:

#### Q.1 Fill in the blanks:
1. Pollutants
2. Sewerage system
3. Sewage
4. Eucalyptus
5. Sewage

#### Q.2 Complete the chart:
- Uses of Clean Water: Cooking, Drinking, Washing, Bathing, Cleaning, Irrigation

#### Q.3 Identify the statements as "Do's and Don'ts":
1. Don’t
2. Don’t
3. Don’t
4. Do

---

Boxed Final Answer:

\[
\boxed{
\text{1. Pollutants, 2. Sewerage system, 3. Sewage, 4. Eucalyptus, 5. Sewage}
}
\]
\[
\boxed{
\text{Uses of Clean Water: Cooking, Drinking, Washing, Bathing, Cleaning, Irrigation}
}
\]
\[
\boxed{
\text{1. Don’t, 2. Don’t, 3. Don’t, 4. Do}
}
\]